1. Field of the Invention
The present invention relates to a robot cleaner.
2. Description of the Related Art
As is well known, a robot cleaner automatically cleans an area by sucking dust and contaminants from a cleaning surface while automatically running around the area without requiring a user's intervention.
One example of such a robot cleaner is illustrated in FIGS. 1 and 2, which will be described briefly below.
FIG. 1 is a perspective view showing a general robot cleaner, with its cover omitted, and FIG. 2 is a bottom view of FIG. 1. Reference numerals indicate elements as follows: robot body 10, dust suction element 20, suction opening 30, sensing element 40, controller 50, and battery 60.
As shown in FIG. 1, a plurality of driving wheels 11, 12 are disposed at both sides of the robot body 10. The robot body 10 is approximately circular in shape, and is provided with a cylindrical cover (not shown).
The dust suction element 20 sucks dust from a surface to be cleaned by using a strong suction force generated at a suction port (not shown) formed in the robot body 10. The dust suction element 20 includes a vacuum motor (not shown) and a dust-collecting chamber (also not shown) for collecting dust drawn in through the suction port by the operation of the vacuum motor.
The suction opening 30 is formed in a side of the bottom of the robot body 10 (FIG. 2) in fluid communication with the suction port (not shown) and has a rotary brush 31 disposed therein for brushing up dust.
The sensing element 40 is arranged along a circumference of the robot body 10 at a predetermined interval to transmit signals to the outside and receive reflected signals. The sensing element 40 includes an obstacle sensor (not shown) and a running distance sensor (not shown).
The controller 50 processes signals received through a transceiver (not shown) and controls the respective parts accordingly. The controller 50 drives the driving wheels 11, 12 in response to the signals from an external control device (not shown) or a remote controller (not shown), and also drives the vacuum motor (not shown) of the dust suction element 20. The controller 50 also controls the operation of the robot cleaner based on the signals received from the sensing element 40.
A robot cleaner with the above-mentioned structure can determine through the sensing part 40 a distance to an obstacle in a cleaning area, such as furniture, office appliances and walls, and selectively drive the driving wheels 11, 12 of the robot body 10, thus automatically changing the running direction of the robot cleaner.
However, the obstacle sensor of the related art robot cleaner cannot detect all obstacles, and, if an unexpected obstacle lies in front of the robot cleaner, the robot cleaner may not respond appropriately. Therefore, a sudden collision with the obstacle causes damages to the cleaner body and other parts.
Also, the related art robot cleaner does not have a function or structure to protect the robot body from a shock due to the sudden collision with the obstacle and to avoid the obstacle. Therefore, a user feels inconvenience, and cleaning efficiency deteriorates.